The purpose of this study is 1) to test the hypothesis that a 10-day ventilatory strategy of minimal ventilation will reduce the incidence of death from chronic lung disease. 2) To test the hypothesis that a 10-day tapering course of a stress dose of corticosteroid will reduce the incidence of death or chronic lung disease. 3) To test the effect of the combined use of early minimal ventilation and corticosteroid therapy on the incidence of death or chronic lung disease.